Several schemes of JS character escape (Escape) __js

First, Json.js

First from the Douglascrockford scheme, should be more people use. Json.js and Json2.js are the same.

Https://raw.github.com/douglascrockford/JSON-js/master/json.js
var meta = {//table of character substitutions< c2/> ' \b ': ' \\b ', ' t ': '
	\\t ',
	' \ n ': ' \\n ',
	' \f ': ' \\f ', '
	\ R ':
	' \ R ', ' ' ': ' \ \ \ ': ' \\\ \'
};
function quote (string) {
	//If The string contains no control characters, no quote characters, and no
	//Backsla SH characters, then we can safely slap some quotes it.
	Otherwise we must also replace the offending characters with safe escape
	//sequences.

	Escapable.lastindex = 0;
	return Escapable.test (String)? ' "'
			+ string.replace (escapable, function (a) {
						var c = meta[a];
						return typeof c = = ' string '? C: ' \\u '
								+ (' 0000 ' + a.charcodeat (0). toString)
										. Slice ( -4);
					}) + ' "': '" ' + string + ' "';
}

two, still taken from D.C big, in Json_parse.js.

Https://raw.github.com/douglascrockford/JSON-js/master/json_parse.js
var escapee = {' '
	: ' ',
	' \ \ \ ': ' \ \ ',
	'/': '/',
	B: ' \b ',
	f: ' \f ',
	N: ' \ n ',
	r: ' \ r ', T:
' \ \ \ \ n '}; string = function () {
	//Parse a string value.
	var hex, I, String = ', uffff;

	When parsing to string values, we must look for and \ characters.
	if (ch = = ' ") {while
		(next)) {
			if (ch = = '" ') {
				next ();
				return string;
			} else if (ch = = ' \ ") {
				next ();
				if (ch = = ' U ') {
					uffff = 0;
					for (i = 0; i < 4; i + 1) {
						hex = parseint (Next ());
						if (!isfinite (hex)) {break
							;
						}
						UFFFF = uffff * + hex;
					}
					string + + String.fromCharCode (UFFFF);
				} else if (typeof escapee[ch] = = = ' String ') {
					string + = Escapee[ch];
				} else {break
					;
				}
			} else {
  string + = ch;
			}}
	Error ("Bad string");
}

three, still for D.C big, in Json_parse_state.js.

Https://raw.github.com/douglascrockford/JSON-js/master/json_parse_state.js
var escapes = {//escapement  Translation table ' \ \ ': ' \ n ', ' ': ' '
	, '/': '/', '
	t ': ' \
	\ ', '/' ': ' \ n ', ' r ': ' \ R ', '
	f ' ' \f ',
	' b ': ' \b '
};
function Debackslashify (text) {
	//Remove and replace any backslash escapement.
	Return Text.replace (/\\: U (. { 4}) | ([^u]) /g, function (A, B, c) {return
				B? String.fromCharCode (parseint (b)): Escapes[c];}

Four, the old version of the Json.js,moontools is also this scheme. Here/[\x00-\x1f\\ "What does]/g mean?"

JSON uses special characters escape
var special = {
	' \b ': ' \\b ',
	' \ t ': ' \\t ',
	' \ n ': ' \\n ',
	' \f ': ' \\f ', '
	\ R ' : ' \ R ', ' ' ': ' \ \ '
	,
	' \ \ ': ' \\\\ '
};
var escape = function (CHR) {return
	SPECIAL[CHR] | | ' \\u '
			+ (' 0000 ' + chr.charcodeat (0). toString). Slice ( -4)
};

function _escape (obj) {return
	' "' + obj.replace (/[\x00-\x1f\\"]/g, Escape) + ' "
}

Five, my current plan, the feeling is relatively simple and clear, but will not have the unknown question. Remain clear.

function Stringas (string) {return
	' "' + string.replace (/(\\|\" |\n|\r|\t)/g, "\\$1") + ' "';
}

finally found there are http://relucent.iteye.com/blog/646016 here